/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ /* * V4L2 subdev userspace API * * Copyright (C) 2010 Nokia Corporation * * Contacts: Laurent Pinchart * Sakari Ailus * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ #ifndef __LINUX_V4L2_SUBDEV_H #define __LINUX_V4L2_SUBDEV_H #include #include #include #include /** * enum v4l2_subdev_format_whence - Media bus format type * @V4L2_SUBDEV_FORMAT_TRY: try format, for negotiation only * @V4L2_SUBDEV_FORMAT_ACTIVE: active format, applied to the device */ enum v4l2_subdev_format_whence { V4L2_SUBDEV_FORMAT_TRY = 0, V4L2_SUBDEV_FORMAT_ACTIVE = 1, }; /** * struct v4l2_subdev_format - Pad-level media bus format * @which: format type (from enum v4l2_subdev_format_whence) * @pad: pad number, as reported by the media API * @format: media bus format (format code and frame size) */ struct v4l2_subdev_format { __u32 which; __u32 pad; struct v4l2_mbus_framefmt format; __u32 reserved[8]; }; /** * struct v4l2_subdev_crop - Pad-level crop settings * @which: format type (from enum v4l2_subdev_format_whence) * @pad: pad number, as reported by the media API * @rect: pad crop rectangle boundaries */ struct v4l2_subdev_crop { __u32 which; __u32 pad; struct v4l2_rect rect; __u32 reserved[8]; }; /** * struct v4l2_subdev_mbus_code_enum - Media bus format enumeration * @pad: pad number, as reported by the media API * @index: format index during enumeration * @code: format code (MEDIA_BUS_FMT_ definitions) * @which: format type (from enum v4l2_subdev_format_whence) */ struct v4l2_subdev_mbus_code_enum { __u32 pad; __u32 index; __u32 code; __u32 which; __u32 reserved[8]; }; /** * struct v4l2_subdev_frame_size_enum - Media bus format enumeration * @pad: pad number, as reported by the media API * @index: format index during enumeration * @code: format code (MEDIA_BUS_FMT_ definitions) * @which: format type (from enum v4l2_subdev_format_whence) */ struct v4l2_subdev_frame_size_enum { __u32 index; __u32 pad; __u32 code; __u32 min_width; __u32 max_width; __u32 min_height; __u32 max_height; __u32 which; __u32 reserved[8]; }; /** * struct v4l2_subdev_frame_interval - Pad-level frame rate * @pad: pad number, as reported by the media API * @interval: frame interval in seconds */ struct v4l2_subdev_frame_interval { __u32 pad; struct v4l2_fract interval; __u32 reserved[9]; }; /** * struct v4l2_subdev_frame_interval_enum - Frame interval enumeration * @pad: pad number, as reported by the media API * @index: frame interval index during enumeration * @code: format code (MEDIA_BUS_FMT_ definitions) * @width: frame width in pixels * @height: frame height in pixels * @interval: frame interval in seconds * @which: format type (from enum v4l2_subdev_format_whence) */ struct v4l2_subdev_frame_interval_enum { __u32 index; __u32 pad; __u32 code; __u32 width; __u32 height; struct v4l2_fract interval; __u32 which; __u32 reserved[8]; }; /** * struct v4l2_subdev_selection - selection info * * @which: either V4L2_SUBDEV_FORMAT_ACTIVE or V4L2_SUBDEV_FORMAT_TRY * @pad: pad number, as reported by the media API * @target: Selection target, used to choose one of possible rectangles, * defined in v4l2-common.h; V4L2_SEL_TGT_* . * @flags: constraint flags, defined in v4l2-common.h; V4L2_SEL_FLAG_*. * @r: coordinates of the selection window * @reserved: for future use, set to zero for now * * Hardware may use multiple helper windows to process a video stream. * The structure is used to exchange this selection areas between * an application and a driver. */ struct v4l2_subdev_selection { __u32 which; __u32 pad; __u32 target; __u32 flags; struct v4l2_rect r; __u32 reserved[8]; }; /* Backwards compatibility define --- to be removed */ #define v4l2_subdev_edid v4l2_edid #define VIDIOC_SUBDEV_G_FMT _IOWR('V', 4, struct v4l2_subdev_format) #define VIDIOC_SUBDEV_S_FMT _IOWR('V', 5, struct v4l2_subdev_format) #define VIDIOC_SUBDEV_G_FRAME_INTERVAL _IOWR('V', 21, struct v4l2_subdev_frame_interval) #define VIDIOC_SUBDEV_S_FRAME_INTERVAL _IOWR('V', 22, struct v4l2_subdev_frame_interval) #define VIDIOC_SUBDEV_ENUM_MBUS_CODE _IOWR('V', 2, struct v4l2_subdev_mbus_code_enum) #define VIDIOC_SUBDEV_ENUM_FRAME_SIZE _IOWR('V', 74, struct v4l2_subdev_frame_size_enum) #define VIDIOC_SUBDEV_ENUM_FRAME_INTERVAL _IOWR('V', 75, struct v4l2_subdev_frame_interval_enum) #define VIDIOC_SUBDEV_G_CROP _IOWR('V', 59, struct v4l2_subdev_crop) #define VIDIOC_SUBDEV_S_CROP _IOWR('V', 60, struct v4l2_subdev_crop) #define VIDIOC_SUBDEV_G_SELECTION _IOWR('V', 61, struct v4l2_subdev_selection) #define VIDIOC_SUBDEV_S_SELECTION _IOWR('V', 62, struct v4l2_subdev_selection) /* The following ioctls are identical to the ioctls in videodev2.h */ #define VIDIOC_SUBDEV_G_STD _IOR('V', 23, v4l2_std_id) #define VIDIOC_SUBDEV_S_STD _IOW('V', 24, v4l2_std_id) #define VIDIOC_SUBDEV_ENUMSTD _IOWR('V', 25, struct v4l2_standard) #define VIDIOC_SUBDEV_G_EDID _IOWR('V', 40, struct v4l2_edid) #define VIDIOC_SUBDEV_S_EDID _IOWR('V', 41, struct v4l2_edid) #define VIDIOC_SUBDEV_QUERYSTD _IOR('V', 63, v4l2_std_id) #define VIDIOC_SUBDEV_S_DV_TIMINGS _IOWR('V', 87, struct v4l2_dv_timings) #define VIDIOC_SUBDEV_G_DV_TIMINGS _IOWR('V', 88, struct v4l2_dv_timings) #define VIDIOC_SUBDEV_ENUM_DV_TIMINGS _IOWR('V', 98, struct v4l2_enum_dv_timings) #define VIDIOC_SUBDEV_QUERY_DV_TIMINGS _IOR('V', 99, struct v4l2_dv_timings) #define VIDIOC_SUBDEV_DV_TIMINGS_CAP _IOWR('V', 100, struct v4l2_dv_timings_cap) #endif id='n41' href='#n41'>41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 
/* SPDX-License-Identifier: LGPL-2.1-or-later */
/*
 * Copyright (C) 2019, Google Inc.
 *
 * bound_method.cpp - Method bind and invocation
 */

#include <libcamera/bound_method.h>

#include "libcamera/internal/message.h"
#include "libcamera/internal/semaphore.h"
#include "libcamera/internal/thread.h"

/**
 * \file bound_method.h
 * \brief Method bind and invocation
 */

namespace libcamera {

/**
 * \enum ConnectionType
 * \brief Connection type for asynchronous communication
 *
 * This enumeration describes the possible types of asynchronous communication
 * between a sender and a receiver. It applies to Signal::emit() and
 * Object::invokeMethod().
 *
 * \var ConnectionTypeAuto
 * \brief If the sender and the receiver live in the same thread,
 * ConnectionTypeDirect is used. Otherwise ConnectionTypeQueued is used.
 *
 * \var ConnectionTypeDirect
 * \brief The receiver is invoked immediately and synchronously in the sender's
 * thread.
 *
 * \var ConnectionTypeQueued
 * \brief The receiver is invoked asynchronously
 *
 * Invoke the receiver asynchronously in its thread when control returns to the
 * thread's event loop. The sender proceeds without waiting for the invocation
 * to complete.
 *
 * \var ConnectionTypeBlocking
 * \brief The receiver is invoked synchronously
 *
 * If the sender and the receiver live in the same thread, this is equivalent to
 * ConnectionTypeDirect. Otherwise, the receiver is invoked asynchronously in
 * its thread when control returns to the thread's event loop. The sender
 * blocks until the receiver signals the completion of the invocation.
 */

/**
 * \brief Invoke the bound method with packed arguments
 * \param[in] pack Packed arguments
 * \param[in] deleteMethod True to delete \a this bound method instance when
 * method invocation completes
 *
 * The bound method stores its return value, if any, in the arguments \a pack.
 * For direct and blocking invocations, this is performed synchronously, and
 * the return value contained in the pack may be used. For queued invocations,
 * the return value is stored at an undefined point of time and shall thus not
 * be used by the caller.
 *
 * \return True if the return value contained in the \a pack may be used by the
 * caller, false otherwise
 */
bool BoundMethodBase::activatePack(std::shared_ptr<BoundMethodPackBase> pack,
				   bool deleteMethod)
{
	ConnectionType type = connectionType_;
	if (type == ConnectionTypeAuto) {
		if (Thread::current() == object_->thread())
			type = ConnectionTypeDirect;
		else
			type = ConnectionTypeQueued;
	} else if (type == ConnectionTypeBlocking) {
		if (Thread::current() == object_->thread())
			type = ConnectionTypeDirect;
	}

	switch (type) {
	case ConnectionTypeDirect:
	default:
		invokePack(pack.get());
		if (deleteMethod)
			delete this;
		return true;

	case ConnectionTypeQueued: {
		std::unique_ptr<Message> msg =
			std::make_unique<InvokeMessage>(this, pack, nullptr, deleteMethod);
		object_->postMessage(std::move(msg));
		return false;
	}

	case ConnectionTypeBlocking: {
		Semaphore semaphore;

		std::unique_ptr<Message> msg =
			std::make_unique<InvokeMessage>(this, pack, &semaphore, deleteMethod);
		object_->postMessage(std::move(msg));

		semaphore.acquire();
		return true;
	}
	}
}

} /* namespace libcamera */